1. Field of the Invention
The present invention relates to a liquid crystal display widely used for an office automation equipment, a television, etc.
2. Description of the Related Art
A liquid crystal display (LCD) generally uses an active matrix system having at least one active device (TFT, MIM, etc.) in each picture element to make the display large-sized and provide high contrast and duty display. However, in the LCD using the general active matrix system, the active device is arranged in the same position as that of the picture element so that numerical aperture is low in comparison with a simple matrix system.
Therefore, there are various kinds of trials for solving such disadvantages. For example, Japanese Patent Application Laying Open (KOKAI) No. 62-10626 proposed a method for connecting the active device to a display picture element through a contact hole without forming the active device on the same plane as that of the picture element, thereby increasing an area for the display picture element. However, in this method, although the numerical aperture is improved, a common electrode and the display picture element are formed through an insulator film so that a parasitic electric capacity is caused between these constructional elements and a drive voltage is thereby increased and the entire capacity is increased. Therefore, when duty is increased, responsibility becomes bad so that there are new problems in which an uneven display such as flicker is caused and no display is provided.